The present invention relates to a soft, putty-like material for lining a denture base, and in more detail, the present invention relates to a soft, putty-like material for lining a denture base, comprising 100 parts by weight of a monomeric compound represented by the formula (I): ##STR2## wherein R.sup.1 represents a hydrogen atom or a methyl group and R.sup.2 represents a residual group formed by removing a hydroxyl group from a fluorine-containing telomer having a molecular weight of 200 to 1500, 3 to 30 parts by weight of a fluorine-containing copolymer, 3 to 30 parts by weight of a C.sub.1 to C.sub.12 -alkyl acrylate or methacrylate and 0.1 to 3.0 parts by weight of a polymerization-initiator.
Although in a method for lining the inner surface of a denture base in order to moderate the occlusal pressure acting on the denture base and to transfer the moderated pressure to the mucous membrane surface in the oral cavity, various materials have been studied as the lining material, no adequate material for that purpose has been found.
In order to solve the above-mentioned problem, the present inventors have proposed a denture base lined with a fluoropolymer (refer to Japanese patent application Laying-Open No. 55-21919). The fluoropolymer lining material for a denture base scarcely absorbs water, is excellent in adhesiveness to the base material of the denture and does not deteriorate for a long time (longer than 2 years) of utilization in the oral cavity. However, the fluoropolymer lining material requires a more complicated operation in applying to a denture base than the commercialized materials and some problems still remain in the extent of softness thereof.
In order to solve the above-mentioned demerits, the present inventors have further proposed a method for lining a denture base with a soft material prepared by mixing the above-mentioned fluoropolymer with a fluorine-containing monomer obtained by bringing a fluorine-containing telomer having a molecular weight of not less than 1500 into esterification with acryloyl chloride or methacryloyl chloride and kneading the thus formed mixture disclosed in U.S. patent application Ser. No. 562,064, filed Dec. 16, 1983 and now abandoned and U.K. Patent Publication No. 2,132,209. Although the soft material used in this method exhibits an excellent effect as a material for moderating and transferring the occlusal pressure on the mucous membrane surface in the oral cavity or a material for stabilizing the denture base during a relatively short time of utilization in the oral cavity, there has still remained the following problem in the soft material in the case where the utilization of longer than one year is desired.
Namely, since the material has been softened by mixing the fluoropolymer with the fluorine-containing monomer, although the lining material has been remarkably improved in the processability, the softness of the material does not change after being lined onto the inner surface of the denture base and during the use of the thus lined denture base.
Accordingly, a flow of the thus lined material is induced by the occlusal pressure resulting in the gradual reduction of the thickness of the layer of the lined material and then in the disappearance of the layer of the lined material finally.
The present inventors have further studied in order to solve the just-mentioned problem. The object of the present invention is to provide a soft material having a fluidity in the stage of processing the material for lining and exhibiting an ideal hardness together with an elasticity after being applied as the lining.